1. Field of the Invention
The present invention relates to the treatment of wood. The invention relates to the treatment of wood in such a way that the chemical structure of all or part of the cellulose is altered to preserve the wood.
2. Description of Related Art
Past wood treatments consist of various chemical and dry kiln loading and unloading techniques for wood. The cellulose of the wood is a reactant of the present invention.
Scientists and researches have been seeking an effective silicon based wood treatment for decades. Studies have suggested that silicon is effective in the treatment of wood. Difficulties have arisen, however, in how to effectively transport the silicon into the wood and keep it there.
Wax resins have also been attempted with unsatisfactory results. Boron compounds may function as insect repellents and may be used in the treatment of wood products. The biggest drawback of the use of boron in the treatment of wood is that it leeches out of the wood too quickly. This leeching has the detrimental effect of leaving the treated wood in a poorly protected state after a relatively short period of time.
Current wood treating techniques require that the wood be dried prior to the treatment process. If the wood is naturally “wet” (or green) the carrier is less efficiently absorbed and cannot effectively distribute the treatment chemical. Wood may also be wet from external sources such as storage, transport, cleaning, weather, etc., and require drying.
Such drying may be accomplished in a variety of ways and at significant expense. Larger wood pieces (i.e. railroad ties, utility poles, timbers, etc.) are typically “air dried”. This process requires that the wood be stored in vast lots where it will naturally dry due to exposure to the sun and air. In addition to the costly management, there is the cost of inventory. Most wood that is air dried is required to sit idle on a lot for 6-12 months. The financial burden of having to carry these enormous inventories of dormant wood has been estimated at nearly $100 million annually for the railroad industry alone.
Another common drying technique is kiln drying. This is a significantly faster process than air drying, but the expense involved in the construction of the drying buildings and the energy utilized to force the wood to dry is significant. Cut timber needs to be kiln or air dried to a level of approximately 14-20% moisture level prior to treatment with existing technologies. This process is costly in terms of time (air drying) or money (kiln drying) and adds a significant cost to the overall treated product. The drying process is necessary to support transport of the carry of the chemicals and provide open volume to accept the treatment solution. A “green” piece of wood will not allow a prior art treatment carrier to enter to an acceptable level.
The treatment methods most commonly used today utilize oil (in the case of creosote) or water (in the case of Chromated Copper Arsenate (CCA)) as the carrier to deliver chemical into the vessels and voids of the wood. These carriers are used with force to place chemicals inside of the wood to treat the wood. There is little or no chemical interaction or reaction with the cellulose of the wood itself. Several factors affect the levels of benefit to the treated wood using current methods including:                The concentration of the chemical in the carrier;        The pressure exerted on the treatment solution to “force” it into the wood; and        The amount of time the wood remains under pressure during the treating process.        
These variables can be adjusted to produce different “grades” of treated wood for different end products. For example, a piece of dimensional lumber will not normally be as thoroughly treated as a railroad cross tie which will be in direct contact with the ground, or common outdoor decking. Typically, the higher the concentration of chemical to its carrier and the longer the treating time the higher the overall cost of treatment.
Water and oil carriers are poor carriers. While they carry the chemical into the wood they also have detrimental effects and reduce the quality of such treatments. A standard cubic foot of untreated wood will absorb as much as 3.5 gallons of water or oil during a normal treatment process. The carrier water or oil remain in the wood adding weight without providing additional treating value. Over time or under changed conditions from those during treating, such carrier may escape the wood and degrade treatment quality. Further, the effect of such carriers contained in the wood over time on the desired treatment or quality of the treated may be varying.
U.S. Pat. No. 5,652,026 to Saka discloses a water based treatment based on the creation of oligomers outside of the wood.
Polish Patent 148704 to Maciejewski teaches the use of a mixture of methylsiloxane, phenylsiloxane and vinyltrichlorosilane in toluene with subsequent curing to make a coating on metal, concrete or wood. The mechanism of this coating involves co-polymerization of the vinylsilane with the siloxanes on curing on the surface of the metal, concrete or wood. The reagent does not react with the metal, concrete or wood but forms a coating on the surface only.
A paper by Stabnikose titled “New Methods of Wood Preservation” discloses the use of organic solvents which are non-hydrophillic and do not allow adequate penetration and retention of silicates in the wood.
Non-hydrophilic organic solvents, such as gasoline and benzene do not mix with water [being highly hydrophobic] and therefore a 5-10% solution in benzene would not penetrate the interior of wet wood. There would be considerable evolution of hydrogen chloride gas that is injurious to workers, environment and damages wood with the benzene.
Nasheri, U.S. Pat. No. 5,871,817 is correct in teaching that boron is introduced into wood, but not bonded in the prior art. It is indicative of the failure of prior art to use boron with bonding reagents. Nasheri is also relevant in that it shows a method in the prior art of introducing additives in the wood. If this type of invention is practiced in advance of the process taught in this application, the boron may be trapped in the wood improving the longevity of the wood product once it is exposed to environmental pressures.
Historically certain treatments have been taught in the treatment of cellulose but only after it is extracted from raw wood and the present invention seeks to improve on that by describing a method and a specific product which can be utilized and created in order to change the structure in native wood, chip wood derivatives, a living tree, in timber, poles or wood composites.